Method of modifying engine oil cooling system

ABSTRACT

A method of modifying the oil cooling system of a diesel engine an engine oil supply outlet located in a horizontal plan includes the steps of removing the original equipment liquid-to-liquid heat exchanger and installing a manifold having an oil outlet port directed to a remote oil cooler and a bypass water passage providing an un-branched flow of water, whereby the flow of oil is directed to a remote oil cooler and the entirety of the flow of water in the bypass water passage is discharged back to the water cooling system of the engine without passing through an oil cooling or water cooling heat exchanger.

FIELD OF THE INVENTION

The present invention relates to a cooling system for an internalcombustion engine and more particularly relates to an oil cooling systemfor both combustion ignition and diesel engines, collectively internalcombustion (IC) engines.

BACKGROUND OF THE INVENTION

Most internal combustion engines require a cooling circuit having acoolant pump, radiator and passageways which circulate a coolant fromthe radiator through the engine block to cool the engine block and themoving components in the engine block. Lubricants, typically a syntheticor mineral-based oil, are utilized to lubricate the relatively movingsurfaces in the engine to counteract friction, reduce wear and reduceoperating temperatures.

However, excessive heat generated in the operation of the engine maycause the oil to degrade and break down losing its lubricating ability.When motor oils break down, they oxidize, thermally degrade and loseviscosity due to shear forces. As a result, many internal combustionengines, particularly high speed diesel engines and high performancecombustion ignition engines, utilize engine block mounted oil coolers.Oil from the engine is passed through a cooler which operates as a heatexchanger with heat exchanger fluid, usually water and glycol, beingprovided from the engine cooling system from either the radiator or theengine block.

However, since the opening temperature of the thermostat in coolingsystems of most internal combustion engines is approximately in therange of 180° to 200° Fahrenheit, an oil cooler utilizing engine coolantas the heat exchanger fluid is limited in its ability to cool the engineoil. By the operation of the cooling system thermostat in many engines,an oil temperature of approximately 200° to 220° F. is maintained sothat the oil effectively lubricates and does not break down or degrade.Further, a low oil temperature is preferred because the oil, in additionto being a lubricant, also serves to cool the internal combustion enginecomponents.

In a coolant to oil cooler system, the engine oil temperature isdependent upon the coolant supply. In the event of even a minor coolantloss, the engine may be damaged as the engine will incur the coolingloss provided both by the coolant and the engine oil.

Accordingly, there exists a need for an improved coolant to oil coolersystem for IC engines which obviates the deficiencies set forth above.

BRIEF SUMMARY OF THE INVENTION

Briefly, the present invention provides a cooling system which replacesthe conventional engine mounted coolant-to-oil heat exchanger with anexternal, high-capacity air-to-liquid heat exchanger. An adaptor blockor manifold is configured to replace an existing Original EquipmentManufacturer (OEM) engine oil cooler and is mounted in place on theengine block utilizing the existing mounting and similar hardware andgaskets that secure the conventional engine oil cooler in place.

The manifold is configured or ported with a passageway to receive thehot, unfiltered oil from the engine and directs the oil to acannister-style oil filter of the type having a replaceable cartridge.The filter may be located immediately adjacent to the manifold or may beat a remote location within the engine compartment. Filtered oil fromthe oil filter is directed to an external heat exchanger, preferably ahigh-capacity air to liquid heat exchanger, which returns the cooled andfiltered oil to the manifold which, in turn, returns cooled and filteredoil to the engine. The system may also include separate bypassfiltration and a particle filtration screen within the manifold, as wellas an oil bleeder valve and an anti-siphon valve. Suitable provision ismade in the manifold for installation of sensors to measure engineoperating parameters such as oil pressure and temperature. Furtherprovision can be made for oil supply to an accessory such as a turbocharger.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other advantages and objects of the present invention willbecome more apparent when taken in conjunction with the followingdescription, claims and drawings in which:

FIG. 1 is a schematic representation of an embodiment of a coolingsystem according to the present invention;

FIG. 2 is a detailed perspective view of the adaptor or manifold sectionof the cooling system shown in FIG. 1;

FIG. 3 is a plan view of the bottom of the manifold showing arepresentative 5 mounting configuration which is adapted to replace theconventional OEM oil cooler;

FIG. 4 is a cross-sectional view of a section of the manifoldillustrating the air bleed valve;

FIG. 5 is a schematic view of an engine oil by-pass that may beincorporated into the cooling system;

FIG. 6 is a schematic view showing the oil by-pass of FIG. 5incorporated in the system of FIG. 1; and

FIG. 7 is a schematic showing a modified system as shown in FIG. 6further including both coolant-to-oil and air-to-oil heat exchangerswith by-pass features to provide warming of the engine oil uponstart-up.

DETAILED DESCRIPTION

Turning now to the drawings, FIG. 1 shows the cooling system of thepresent invention mounted in place on the cylinder block B of an ICengine which is represented schematically by dotted lines. The mountinglocation may vary depending on the engine configuration. The IC enginemay be a CI or diesel having an engine mounted cooler 8 which is removedand replaced with a manifold 11. The system indicated by the numeral 10includes a housing or manifold 11 which may be cast and machined from asingle block or billet of material such as steel or aluminum. Preferablythe underside of the manifold, as best seen in FIG. 3, is machined toconform to the mounting configuration of the conventional coolant-to-oilcooler mounted on the engine block which cooler has been removed, havingbolt holes 19 conforming to the existing bolt pattern. FIG. 3 shows arepresentative 5 mounting for a 6.0 L International® VT365 diesel enginealso known as the 6.0 L Ford® Powerstroke diesel engine (hereinafterreferred to as the “6.0 L VT365 diesel engine”) found in a 2004 FordF350 truck. If the engine has not been originally equipped with an oilcooler, suitable mounting provision for the manifold must be made whichmay involve appropriate modifications such as tapping the engine blockat suitable locations for mounting the manifold and installing suitablehydraulic lines.

However, in most cases, the cooling system of the present invention willbe applicable and is adapted for replacement of a conventional enginemounted IC coolant-to-oil cooler and the following description proceedson that basis. Once the existing oil cooler is removed, the manifold 11is secured using suitable hardware and gaskets to position and mount thehousing on the engine block B. Port or passageway 25 in the underside ofthe manifold aligns with a port P in the engine block B through whichhot, unfiltered oil is directed to the manifold 11. The oil enters themanifold at passageway 25 and flows through the manifold 11 exiting atport 13. Port 13 is connected by a hydraulic line 20 to oil filter 14.Line 20 has an anti-siphon check valve 21 to prevent reverse flow of oilthrough line 20. The oil filter 14 may be located immediately adjacentthe manifold 11 or may be at a convenient location in the enginecompartment considering engine size, available space and otherinstallation restrictions.

The oil filter 14 is a canister-type and has an inlet 22 whichcommunicates with and receives oil from the manifold. The housing has alower screw or spin-on body 24 which is removable. The body 24 containsa suitable element 26 of a filtering material such as paper or fiberwhich is periodically replaceable. Preferably the filter is aconventional filter available from manufacturers such as FRAM, WIX andothers. Particulates and contaminants are substantially removed as theoil passes through the filter element 26.

The oil exiting oil filter 14 is then directed to an external heatexchanger, preferably an air-to-liquid heat exchanger 15. The externalheat exchanger may be a tube or plate design and is preferably of thetube type having a tube 28 carrying the oil to be cooled which extendsin serpentine fashion within the heat exchanger housing. Because air isa relatively poor conductor of heat, the heat transfer area between theair passing over the tubes is increased by adding fins 30 to the tubes.The heat exchanger 15 is mounted in a location remote from the locationof the OEM heat exchanger, preferably located in the vehicle to receivesubstantial airflow, for example at the front of the vehicle immediatelyadjacent and in front of the radiator for the engine cooling system.Ducting may be provided to increase airflow to the heat exchanger 15.

The oil which has been cooled and filtered is returned to an inlet port17 on the manifold 11 via line 32. The inlet port 17 connects withinternal passageway 34 communicating with outlet port 12. The outletport 12 on the bottom of the manifold is aligned and communicates withthe engine block port P so the cooled and filtered oil returns to theengine to provide lubrication. An additional outlet port 12A, as seen inFIG. 3, is provided to supply cooled and filtered oil to the highpressure oil pump.

Additional filtering may be provided by a bypass filter 18. The bypassfilter 18 is a separate filter and may be of the cannister type asdescribed with reference to filter 14. A bypass line 36 removes aportion of the cooled and filtered oil prior to the oil entering intoport 17 and directs the oil to the inlet of the bypass filter 18. Thebypass filter 18 has an outlet which directs the flow via line 38 toport 12 to be returned to the engine.

Passageway 34 connected to port 17 may also be intercepted bypassageways 40, 42 and 44 which are suitably threaded for connection togauges such as the pressure gauge at 40, temperature gauge 42 and oilfeed for the turbo at 44. Other sensing locations can also be providedto measure other operating parameters. Provision is made in the manifoldto circulate coolant through the engine cooling system. Coolant entersthe manifold at port 55 and exits at port 56 where it is returned to theengine cooling system without passing through an oil or water coolingheat exchanger. The coolant thus returned to the engine cooling systemis circulated by a water pump through the existing passages in theengine block and radiator.

In many engines, metal particles will be released during operation. Inaddition to metal particles, sand used in the engine block castingprocess and retained in the engine may also be released. These larger,particulate materials can be harmful to the engine and may also quicklyclog or reduce the effectiveness of the filters, such as the F1A filter,which are primarily intended to remove finer particulate materials.

The oil cooling system of the present invention may be provided with aparticulate filter internal within the manifold 11 to trap and removelarger particulates which may otherwise quickly impair the effectivenessof element type filters. A cavity 50 is provided within the housing andremovably receives a screen 52 having a mesh in the 0.003 to 0.005 inchrange. The screen is accessible and removable by detaching the manifoldfrom the engine block or access may be provided through a suitableaccess panel 54 on the manifold. A portion of the cooled and filteredoil entering the manifold at port 17 may be internally diverted to thecavity 50 and onto a surface of the particulate screen 52. The oil will,due to pressure existing in the system and gravity, flow downwardlythrough the screen to ports 12 and 12A returning to the engine.Particulate material will collect on the screen 52 and may beperiodically removed by accessing the screen by removal of the manifoldor through an access panel as described above.

An oil bleed valve 16 may be provided as seen in FIG. 4. The oil bleedvalve 16 is in a passageway 60 communicating with passageway 34. A ball65 is held in place by a spring 66. The spring 66 is retained by a plug68 with a small orifice 70. Passageway 60 is closed by a plug 72. Whenthe pressure in passageway 34 exceeds a predetermined level, the ball 65will open returning oil to the engine crank case via line 62, allowingair within the engine's oil system to be removed.

FIGS. 2 and 3 illustrate a representative configuration for the manifoldand for the configuration of the passageways within the manifold whichmay be utilized in connection with the cooling system of the presentinvention. However, it will be appreciated that the particularconfiguration shape of the manifold may vary with the intendedinstallation. It will also be appreciated that the present system hasbroad utility and application to various internal combustion engines ofdifferent types and displacement. Accordingly, while the presentinvention has been described in detail with reference to a preferredembodiment it is to be understood that the disclosure has onlyillustrated an exemplary embodiment.

FIGS. 5 and 6 are schematics which show a by-pass 100 that may beincorporated into the system 10 shown in FIG. 1. Referring to FIG. 5,which 5 shows the by-pass 100 which has a housing 102 having an inlet106 and outlet 108 connected by a passageway 110 is intercepted by apressure by-pass line 112 and a temperature by-pass line 114 both ofwhich communicate with by-pass outlet 120. A pressure control valve 122such as a spring-biased valve is located in line 112. The valve 122 maybe a direct acting relief valve which opens at a fixed pre-set pressureestablished by a spring which may be adjusted by a spring adjustmentscrew. The valve is set to by-pass fluid to the outlet when thedifferential pressure between the inlet and outlet of the oil cooler isabove the setting, typically about 40-50 psi, which differential mayinitially occur during start-up before the pressure in the systemgenerated by the engine oil pump has fully pressurized the engine oilsystem.

Similarly, the temperature by-pass line includes a thermostatic control126 which has a selected opening temperature generally between 170-200°F. The thermostat control will block flow through the by-pass 100 anddirect the oil flow to outlet 120 until such time as the temperature ofthe oil reaches a temperature at which the thermostat is set to open.Thus, the oil entering the by-pass 100 will be directed to the coldby-pass outlet 120 if either: (1) the engine oil is below apredetermined temperature by the closed thermostat 126 or (2) the oilpressure differential between the inlet and outlet of the oil coolingheat exchanger 15 is greater than the differential setting of thecontrol valve 122.

In FIG. 6, the by-pass 100 is shown in the system 10 of FIG. 1. Thesystem 10 has been simplified in FIG. 6 but is as described in greaterdetail with reference to FIG. 1 which description is incorporated hereby reference. The by-pass 100 is located adjacent the air-to-liquid heatexchanger 15, either ahead of the heat exchanger 15 or downstream of thedischarge. In FIG. 6, the by-pass 100 is shown ahead of the heatexchanger 15. The outlet 108 of the by-pass 100 is in communication withthe heat exchanger 15. The by-pass outlet 120 is connected via by-passline 130 to line 32 leading to the manifold 11. Accordingly, if engineoil is below a predetermined temperature or if a predetermined pressuredifferential exists between the inlet and outlet of oil exceeding thesetting of control valve 122, oil will be by-passed through by-pass 100allowing the system oil temperature and pressure to build to acceptablelevels due to engine operation. This typically may take 4 or 5 secondsafter start up. The by-pass 100 lessens stress and wear on enginecomponents due to oil conditions which reduce the effectiveness of thelubrication.

In FIG. 7, a modification of the system 10 of Claim 1 is shown which isadopted for engines which operate in colder climates. They system ofFIG. 7 is indicated by the numeral 200 and includes a manifold 11secured to the engine block B as described with reference to FIG. 1. Thehot, unfiltered oil from the engine is directed to a filter 14 by line20 and exits the filter 14 to tee 202 having outlet lines 232, 232A.Line 232 is directed to by-pass 100 located adjacent an air-to-liquidheat exchanger 15. The by-pass 100 is as described with reference toFIGS. 5 and 6. The heat exchanger 15 is as has been previously describedwith reference to FIG. 1. The by-pass 100 will direct engine oil eitherto the heat exchanger 15 or, if the temperature or pressure conditionsof the oil are within predetermined by-pass parameters, the oil will beby-passed around the heat exchanger 15 via line 130 to line 32.

The engine oil discharged through line 232A is directed to acoolant-to-oil heat exchanger 225 which receives liquid coolant at inletport 226 from the engine cooling system under pressure from the enginewater pump 230 which is recirculated from the heat exchanger via line234. The thermostat in the engine cooling system will operate at apreset opening temperature of typically around 190°-200° F. and becirculated by the water pump 230 through the heat exchanger 225 to warmthe oil initially flowing through the heat exchanger from the filter. Asthe engine warms and the engine oil is heated, the heat exchanger 225will operate to maintain the oil temperature at about the temperature ofthe engine coolant fluid from the water pump. Thus, the heat exchangerinitially assists in heating the engine oil during the initial enginestart-up and thereafter will operate to maintain the oil at anacceptable temperature.

The dual system of FIG. 7 having both an air heat exchanger and a liquidheat exchanger in parallel enhances or increases the effective heatexchange area and operates to cool engine oil during operation and willheat or warm the engine oil during initial start-up and has particularapplication to engines operating in colder climates or conditions.

It will be obvious to those skilled in the art to make various changes,alterations and modifications to the invention described herein. To theextent such changes, alterations and modifications do not depart fromthe spirit and scope of the appended claims, they are intended to beencompassed therein.

What is claimed is:
 1. A method of modifying an oil cooling system for avehicle having a diesel engine, the diesel engine having an engine blockwith an engine oil supply inlet, an engine water coolant outlet, anengine oil supply outlet located in a horizontal plane, an oil pump, anda water cooling system with a water pump, the engine having an originalequipment liquid-to-liquid heat exchanger in which heat from the oil istransferred to the water cooling system, the original equipmentliquid-to-liquid heat exchanger having a predetermined mountingconfiguration, the original equipment liquid-to-liquid heat exchangerfurther comprising an oil inlet, an oil outlet, a water inlet, and awater outlet each in a predetermined location, the method comprising:(a) removing the original equipment liquid-to-liquid heat exchanger fromthe engine block; (b) attaching a manifold to the engine block, saidmanifold having an oil inlet port for receiving a flow of oil from theengine oil supply outlet, the manifold further comprising an oil outletport, the manifold being sized and shaped to match the mountingconfiguration of the original equipment liquid-to-liquid heat exchanger,the manifold further being configured to position said oil inlet port ina horizontal plane adjacent the engine oil supply outlet of the engineblock at the location of the oil inlet of the original equipmentliquid-to-liquid heat exchanger whereby the manifold is capable ofreceiving the flow of oil from the engine oil pump without leakage; (c)mounting a remote oil cooling heat exchanger in a location distal fromthe location of the original equipment liquid-to-liquid heat exchanger,the remote oil cooling heat exchanger receiving a flow of oil from saidmanifold and cooling the flow of oil prior to returning the flow of oilto the engine oil supply, the flow of oil being returned to the enginefrom the remote oil cooling heat exchanger via a passageway in saidmanifold; (d) the manifold further comprising a water passage providingan un-branched flow of water, the water passage having a water inletport and a water outlet port, the manifold being configured to positionthe water inlet port adjacent the engine water coolant outlet of theengine block at the location of the water inlet of the originalequipment liquid-to-liquid heat exchanger, the manifold further beingconfigured to position the manifold water outlet port so that theentirety of the flow of water in the bypass water passage is dischargedback to the water cooling system of the engine without passing throughan oil cooling or water cooling heat exchanger.
 2. The method of claim1, wherein: the vehicle has a front end and a rear end, and the methodfurther comprises mounting the remote oil cooling heat exchangerproximal the front end of the vehicle.
 3. The method of claim 2,wherein: the vehicle comprises a radiator for cooling the enginecoolant, and the method further comprises mounting the remote oilcooling heat exchanger proximal the vehicle radiator.
 4. The method ofclaim 1, wherein said remote heat exchanger is an air-to-liquid heatexchanger.
 5. The method of claim 4, wherein said air-to-liquid heatexchanger is a tube-and-fin heat exchanger.
 6. The method of claim 1,wherein: the manifold includes at least one sensor port.
 7. The methodof claim 1, wherein: the manifold includes a horizontally disposedrecess adapted to receive a particulate filter and the method furthercomprises mounting a particulate filter in the recess, the particulatefilter having a filter screen with a mesh size of at least 0.003 inchreceiving a portion of the flow of oil from said manifold.
 8. The methodof claim 7 wherein said filter screen is removable.
 9. The method ofclaim 1, further comprising: mounting an oil filter to receive a flow ofoil from the outlet port of the manifold.
 10. The method of claim 9,further comprising mounting the oil filter to discharge the flow of oilfrom the oil filter to the remote oil cooling heat exchanger.